Etrema Products, Inc. and Applied Research Laboratory at The Pennsylvania State University demonstrated during Phase I that by utilizing the “delta-E” effect in magnetostrictive materials, the resonant frequency of a split ring transducer can be shifted by over 200 Hz for a low frequency transducer. A variable reluctance driver helps achieve source levels in excess of 210 dB with a potential 80% cost reduction as compared with a similar PZT transducer. The Phase II effort will focus on building hardware and verifying the performance and cost, and scalability of the transducer. Objectives of the Phase Base II effort are: 1. Identify the most viable compliance hinge mechanism and controller algorithm, 2. Demonstrate feasibility of the variable reluctance driver, 3. Demonstrate technical feasibility of the transducer including the controller. The Phase II Option Objectives are: 4. Identify performance limits of the transducer by testing the first article transducers, 5. Demonstrate the transition potential of the technology by optimizing the transducer design. Successful completion of the Phase II and Phase II Option efforts will result in a low-cost, low-frequency transducer design that can be transitioned to Navy applications.